#ifndef __ASM_ALPHA_FPU_H #define __ASM_ALPHA_FPU_H /* * Alpha floating-point control register defines: */ #define FPCR_DNOD (1UL<<47) /* denorm INV trap disable */ #define FPCR_DNZ (1UL<<48) /* denorms to zero */ #define FPCR_INVD (1UL<<49) /* invalid op disable (opt.) */ #define FPCR_DZED (1UL<<50) /* division by zero disable (opt.) */ #define FPCR_OVFD (1UL<<51) /* overflow disable (optional) */ #define FPCR_INV (1UL<<52) /* invalid operation */ #define FPCR_DZE (1UL<<53) /* division by zero */ #define FPCR_OVF (1UL<<54) /* overflow */ #define FPCR_UNF (1UL<<55) /* underflow */ #define FPCR_INE (1UL<<56) /* inexact */ #define FPCR_IOV (1UL<<57) /* integer overflow */ #define FPCR_UNDZ (1UL<<60) /* underflow to zero (opt.) */ #define FPCR_UNFD (1UL<<61) /* underflow disable (opt.) */ #define FPCR_INED (1UL<<62) /* inexact disable (opt.) */ #define FPCR_SUM (1UL<<63) /* summary bit */ #define FPCR_DYN_SHIFT 58 /* first dynamic rounding mode bit */ #define FPCR_DYN_CHOPPED (0x0UL << FPCR_DYN_SHIFT) /* towards 0 */ #define FPCR_DYN_MINUS (0x1UL << FPCR_DYN_SHIFT) /* towards -INF */ #define FPCR_DYN_NORMAL (0x2UL << FPCR_DYN_SHIFT) /* towards nearest */ #define FPCR_DYN_PLUS (0x3UL << FPCR_DYN_SHIFT) /* towards +INF */ #define FPCR_DYN_MASK (0x3UL << FPCR_DYN_SHIFT) #define FPCR_MASK 0xffff800000000000L /* * IEEE trap enables are implemented in software. These per-thread * bits are stored in the "ieee_state" field of "struct thread_info". * Thus, the bits are defined so as not to conflict with the * floating-point enable bit (which is architected). On top of that, * we want to make these bits compatible with OSF/1 so * ieee_set_fp_control() etc. can be implemented easily and * compatibly. The corresponding definitions are in * /usr/include/machine/fpu.h under OSF/1. */ #define IEEE_TRAP_ENABLE_INV (1UL<<1) /* invalid op */ #define IEEE_TRAP_ENABLE_DZE (1UL<<2) /* division by zero */ #define IEEE_TRAP_ENABLE_OVF (1UL<<3) /* overflow */ #define IEEE_TRAP_ENABLE_UNF (1UL<<4) /* underflow */ #define IEEE_TRAP_ENABLE_INE (1UL<<5) /* inexact */ #define IEEE_TRAP_ENABLE_DNO (1UL<<6) /* denorm */ #define IEEE_TRAP_ENABLE_MASK (IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE |\ IEEE_TRAP_ENABLE_OVF | IEEE_TRAP_ENABLE_UNF |\ IEEE_TRAP_ENABLE_INE | IEEE_TRAP_ENABLE_DNO) /* Denorm and Underflow flushing */ #define IEEE_MAP_DMZ (1UL<<12) /* Map denorm inputs to zero */ #define IEEE_MAP_UMZ (1UL<<13) /* Map underflowed outputs to zero */ #define IEEE_MAP_MASK (IEEE_MAP_DMZ | IEEE_MAP_UMZ) /* status bits coming from fpcr: */ #define IEEE_STATUS_INV (1UL<<17) #define IEEE_STATUS_DZE (1UL<<18) #define IEEE_STATUS_OVF (1UL<<19) #define IEEE_STATUS_UNF (1UL<<20) #define IEEE_STATUS_INE (1UL<<21) #define IEEE_STATUS_DNO (1UL<<22) #define IEEE_STATUS_MASK (IEEE_STATUS_INV | IEEE_STATUS_DZE | \ IEEE_STATUS_OVF | IEEE_STATUS_UNF | \ IEEE_STATUS_INE | IEEE_STATUS_DNO) #define IEEE_SW_MASK (IEEE_TRAP_ENABLE_MASK | \ IEEE_STATUS_MASK | IEEE_MAP_MASK) #define IEEE_CURRENT_RM_SHIFT 32 #define IEEE_CURRENT_RM_MASK (3UL<<IEEE_CURRENT_RM_SHIFT) #define IEEE_STATUS_TO_EXCSUM_SHIFT 16 #define IEEE_INHERIT (1UL<<63) /* inherit on thread create? */ /* * Convert the software IEEE trap enable and status bits into the * hardware fpcr format. * * Digital Unix engineers receive my thanks for not defining the * software bits identical to the hardware bits. The chip designers * receive my thanks for making all the not-implemented fpcr bits * RAZ forcing us to use system calls to read/write this value. */ static inline unsigned long ieee_swcr_to_fpcr(unsigned long sw) { unsigned long fp; fp = (sw & IEEE_STATUS_MASK) << 35; fp |= (sw & IEEE_MAP_DMZ) << 36; fp |= (sw & IEEE_STATUS_MASK ? FPCR_SUM : 0); fp |= (~sw & (IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF)) << 48; fp |= (~sw & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE)) << 57; fp |= (sw & IEEE_MAP_UMZ ? FPCR_UNDZ | FPCR_UNFD : 0); fp |= (~sw & IEEE_TRAP_ENABLE_DNO) << 41; return fp; } static inline unsigned long ieee_fpcr_to_swcr(unsigned long fp) { unsigned long sw; sw = (fp >> 35) & IEEE_STATUS_MASK; sw |= (fp >> 36) & IEEE_MAP_DMZ; sw |= (~fp >> 48) & (IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF); sw |= (~fp >> 57) & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE); sw |= (fp >> 47) & IEEE_MAP_UMZ; sw |= (~fp >> 41) & IEEE_TRAP_ENABLE_DNO; return sw; } #ifdef __KERNEL__ /* The following two functions don't need trapb/excb instructions around the mf_fpcr/mt_fpcr instructions because (a) the kernel never generates arithmetic faults and (b) call_pal instructions are implied trap barriers. */ static inline unsigned long rdfpcr(void) { unsigned long tmp, ret; #if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67) __asm__ __volatile__ ( "ftoit $f0,%0\n\t" "mf_fpcr $f0\n\t" "ftoit $f0,%1\n\t" "itoft %0,$f0" : "=r"(tmp), "=r"(ret)); #else __asm__ __volatile__ ( "stt $f0,%0\n\t" "mf_fpcr $f0\n\t" "stt $f0,%1\n\t" "ldt $f0,%0" : "=m"(tmp), "=m"(ret)); #endif return ret; } static inline void wrfpcr(unsigned long val) { unsigned long tmp; #if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67) __asm__ __volatile__ ( "ftoit $f0,%0\n\t" "itoft %1,$f0\n\t" "mt_fpcr $f0\n\t" "itoft %0,$f0" : "=&r"(tmp) : "r"(val)); #else __asm__ __volatile__ ( "stt $f0,%0\n\t" "ldt $f0,%1\n\t" "mt_fpcr $f0\n\t" "ldt $f0,%0" : "=m"(tmp) : "m"(val)); #endif } static inline unsigned long swcr_update_status(unsigned long swcr, unsigned long fpcr) { /* EV6 implements most of the bits in hardware. Collect the acrued exception bits from the real fpcr. */ if (implver() == IMPLVER_EV6) { swcr &= ~IEEE_STATUS_MASK; swcr |= (fpcr >> 35) & IEEE_STATUS_MASK; } return swcr; } extern unsigned long alpha_read_fp_reg (unsigned long reg); extern void alpha_write_fp_reg (unsigned long reg, unsigned long val); extern unsigned long alpha_read_fp_reg_s (unsigned long reg); extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val); #endif /* __KERNEL__ */ #endif /* __ASM_ALPHA_FPU_H */